Keane, who was linked with the vacant Celtic manager's job before agreeing to become Paul Lambert's No. 2, is excited by the prospect of helping the Midlands club improve on their finishing position of 15th in the Premier League:

Roy Keane: "I am delighted to be joining Villa and I look forward to what promises to be an exciting challenge.” #AVFC#WelcomeRoy

The former Manchester United captain—feared throughout the sport for his ferocious reputation—heads to Villa after gaining managerial experience with Sunderland and Ipswich Town, before joining Martin O'Neill as assistant manager in the Republic of Ireland camp.

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His only managerial silverware to date remains the 2006-07 Championship crown he won with the Black Cats, taking Sunderland into the Premier League during the first season after he retired from playing.

Bryan Swanson of Sky Sports confirmed Keane will maintain his position with the national side, ensuring he has quite a workload to deal with in the 2014-15 season:

FAI statement: "Roy Keane to remain with Republic of Ireland and combine Assistant Manager role with Aston Villa."

The hard-tackling, no-nonsense talker is famed for his explosive aggression and opinionated nature, both of which have often spilled over during his professional career. Keane received 69 yellow cards and seven reds during his Premier League career, as reported back in 2008, via the Daily Mail.

He is famed for a horrific tackle on Alf-Inge Haaland and an argument with former Ireland boss Mick McCarthy that saw Keane leave the 2002 World Cup early. Even so, Keane's fire played a huge role in his ascension as one of the domestic league's most successful midfielders.

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Lambert is pleased to add such a renowned individual to his coaching staff, as reported by Brian Doogan on Villa's official website:

Roy has a great knowledge of football, on the coaching side as well, and he'll be a great asset and a big help to everybody here at Aston Villa Football Club. I'm really looking forward to working with him and I'm delighted that he's here.

Keane's appointment looks to add stability after a difficult start to the summer for Villa, summarised by Randy Lerner's decision to sell the club that Stuart James of The Guardian believes is "on the road to nowhere."

Although Lerner admitted he was trying to "create something very special" at the mid-point of his tenure in 2010, a combination of dwindling investment, poor managerial appointments and failings on the pitch have failed to do so.

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Lambert and Keane have a massive job on their hands if Villa are to return to the upper echelons of the Premier League table. Clubs around the top flight ever-presents continue to improve, while the Villains have slowly lost their spark. The club houses some real quality in the shape of Christian Benteke, Ron Vlaar and Brad Guzan, but the squad is devoid of strength in depth.

Keane understands what it takes to build a winning squad—having represented the beating heart of multiple teams at United—and is sure to aid Lambert's attempts to improve his side's work-rate, confidence and ruthlessness.

Villa fans will now hope to see additional players brought in to beef up a team that has the potential to compete far more avidly than it managed last season.